This invention relates to laser systems, more particularly to a method and laser system for synchronous generation and amplification of tunable vacuum ultraviolet laser radiation.
Heretofore a traveling wave discharge system has been set forth in an article by John D. Shipman, Jr. in Applied Physics Letters, 10, Vol. 1, January 1967, pp 3-4. The teaching of this traveling wave system has been used by others to produce a traveling wave excited gas laser. Such a system has been set forth in U.S. Pat. Nos. 3,729,689 and 3,821,664, as well as in several published articles. Such as, "A Fast-Rise-Time Excitation System for Production of Vacuum Ultraviolet Laser Emission" by R. W. Waynant and J. D. Shipman, Jr., IEEE J. Quantum Electronics, Vol. QE7, No. 6, June 1971, p 282; and "Vacuum Ultraviolet Laser Emission from CIV," by Ronald W. Waynant, Applied Physics Letters, Vol. 22, No. 8, 15 April 1973, pp 419-420. Additional published articles are listed as references in the latter article. In addition, mixing of dye laser frequencies has been demonstrated by Harris and by Hodgson.
Generation of tuneable short wavelength laser pulse generally involves utilization of a laser or fast flashlamp to pump two dye lasers. These pulses are then added frequency-wise in a vapor with appropriate non-linear susceptibility and dispersion characteristics such as a strontium cell. The resulting low power pulse, which suffers due to the inefficiency of the non-linear addition process, must be amplified in order to repeat the mixing process and generate shorter wavelengths. Amplification with gas laser discharge systems cannot be accomplished because of the difficulties of synchronizing the lasers or flashlamps which excite the dye and generate the tunable pulse with the short lived gain (.perspectiveto.1ns) of available amplifiers.